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From: torkil@Pacesetter.COM (Torkil Hammer)
Newsgroups: alt.msdos.programmer,comp.sys.ibm.pc.misc
Subject: Re: ATI VGA Wonder programming info
Message-ID: <1990Sep12.220246.1659@Pacesetter.COM>
Date: 12 Sep 90 22:02:46 GMT
References: <3019@amc-gw.amc.com> <923@gvlv2.GVL.Unisys.COM>
Organization: Pacesetter Systems Inc., Sylmar, CA
Lines: 24

Notice the part about finding out about supported modes.  I did
exactly so for all the 256 modes and found to my surprise that
additional undocumented modes are:

0x55, a 1024 by 768 by 16 colors graphics mode similar to 0x54 and 0x12
in encoding.  It does the same as 0x65 but uses the customary "planar"
encoding with 8 pixels per byte, each pixel occupying 4 planes.
The 0x55 BGI driver is remarkably faster than the 0x65 one,
and the use of the palette is simpler for the 0x55.

0x5b, a text mode with 30 lines of 80 chars using the 16 bit font,
34 x 80 using the 14 bit font, and 60 x 80 very flat lines using
the 8 bit font.  This is because it gives 480 vertical scan lines, while
mode 0x03+ gives 400, otherwise 0x5b and 0x03+ are identical.
(0x03+ is the VGA mode you get when a multisync terminal is connected).

In addition, it appears that 0x53 and 0x54 does the same.  Their mode
tables have the same address in the ATI BIOS rom.  The same observation
holds true for 0x00,0x01 and 0x02,0x03.

Try it, you'll like it.  Your modeage may vary.  My ATI card is from
July '89.  Of course, you need a multisync monitor to have these modes.

Torkil Hammer